Engineering exciton dynamics in self-organized quantum dots

The dynamics of excitons localized in self-organized In(Ga)As/GaAs quantum dots is investigated, demonstrating a pronounced influence of the actual structural properties on the relaxation and recombination processes. The complex confining potential in such strained, inhomogeneous quantum dots affects the electron/hole overlap and, thus, the oscillator strength as well as the Fröhlich coupling to LO-phonons. Both relaxation- and recombination-limited intradot exciton dynamics are demonstrated and correlated to the structural properties of the quantum dots. The results suggest a unique potential to engineer exciton dynamics in self-organized quantum dots, utilizing the bandwidth of structural properties obtainable in strained heteroepitaxy.